Why Cameron Diaz & Alex Rodriguez Make a Good Couple: Joanna Garcia-Swisher Explains!

At last night's Bad Teacher premiere in NYC, Cameron Diaz's good friend Joanna Garcia-Swisher came out to support the star.

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Asked by reporters why Cameron and boyfriend Alex Rodriguez made such a good couple, she stated simply, "Because they're good people!"

Earlier in the evening while appearing on Late Night With David Letterman, Cameron playfully said that Dave could call Alex her boyfriend. "I do," she said. When asked how they met, she told Dave, "Funny enough, I stepped on him with my heel! I staked him." (This was in reference to accidentally stepping on Dave's foot earlier.)

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Joanna also gave another couple, Kim Kardashian and Kris Humphries, some advice for their wedding day: Don't leave each other's sides!

"Do not separate that day," she said. "My husband and I held hands the entire night and the best memory we have is the memory that we share."

So far it's working out well, as Joanna said she loves being a newlywed! "It's amazing. It's the best thing on the planet."